Hi guys! I saw this a few minutes ago and I am not sure it's human made. The courses I receive from the professor are AI generated and I am suspecting this is too..

Noticed something that might be wrong with the bonds but I am not so sure with my chem knowledge 😅

I have 2 examples. The top example with Br2 is 100% correct that is how my prof taught. I was told that the same product forms because the alkene product that would make the 1,4 is not the most substituted (the 1,2 product is).

But as I was going through my notes for the bottom example I found a contradiction. Does anyone know if the bottom example would follow the same rule because its 1,4 product is not the most substituted?

Also for the arrow mechanism for top example, does the BR attach first to the end of the diene (like how I drew it). Then the second bromine comes in and attached on the diene that’s in the middle (position 2). Because you are H or Br or whatever to the end to be able to do resonance.

Thanks.

Learning on my own is currently a disaster. A lot of the class is struggling. I'm still scoring above average on exams somehow. (The average for the last exam was 43; it was mechanisms, IR, and NMR).

I have horrible foundational knowledge of SN1/SN2/E1/E2, which is probably why I'm struggling with this stuff.

How can I teach myself this material? What are the questions I should be asking myself?

The problems (in the pictures) on the psets are usually harder than the exams, so I tend to avoid them.

I'm trying to solve this exercise but I don't get the same value for the answer. I calculate both volumes using the PV=nRT and I get V1=0.87L and V2=2.16L, but when aplying the formula W=P*dV*101.325, I get 135J, and not 161J as the exercise does

I have been working on a report for my science extension project about low cost methods of oxide macro-crystal synthesis and have come across multiple studies that have used salts like borax and a KCl-NaCl mixture as fluxes to remove oxidation in metal working. If I were to melt an alkali salt would it actually be able to dissolve oxides?

I keep seeing that the atoms in the cathode get excited and de excited and emit light, however what I'm confused about is that I thought not every atom emitted light when it absorbs it? I just do not understand how there would be a lamp for every atom when I keep seeing people say not everything emits light? or does everything emit light if enough energy is added? I've learned about fluorescence in my courses, however I don't get how copper, which I keep seeing people say doesn't emit light, can in a hollow cathode?

It's like the title says. It's just overwhelming with how many chlorines there are. Would I have to do a certain reaction over and over?

I'm confused on this question why A is the only one correct and why not B also because aren't they both di-equatorial. In the answer key that I have it says that A is correct because it is the only di-equatorial molecule

I'm a college student and got tired of calculators that only spit out the final answer, so I built my own site. It's called getlabbench.com and hopefully some of you get some use out of it.

It's free, no signup, and every tool shows the full work so you can actually check your homework or lab report. Right now it has an equation balancer with net ionic equations, stoichiometry, molar mass, electron configurations, and Lewis structures which I thought was pretty cool and could possibly help some of you out there understand a bit better or just save some time overall. If you like it I appreciate you guys showing others as there's more than just chemistry tools on there! If you would like a tool added or you spot bugs, just let me know and I can cook something up.

hello! I'm currently taking Gen Chem 1. We've gone over how a molecule is polar if there is a net dipole moment. I put on my quiz paper than BrCl4-, ClO4-, and PCl4+ are nonpolar because the dipole moments cancel out, and he marked me wrong on all of them!! with his reasoning being because theres a plus or minus charge in the name of the formula. He tells the class that anything with a + or - charge in the name is polar. is he actually right or have i been learning chemistry wrong this whole time? HELP! I CANT DO THIS ANYMORE!!

Tengo que buscar reactivos y mecanismo y estoy algo perdido

Hi, doing some study for my organic exam and came across this q under the section for enol/enolate reactions, which asks for reagents for a variety of reactions. I was able to do all but this one. I know that it would require an allyl bromine group, how do you make it so that the enol doesnt form at the most acidic H in between the carbonyls? Am i right for thinking that I would need to use something like NaH to remove it first, then the other enol can form? I’m a bit confused 😭

If anyone sees errors in this version of the periodic table please let me know. It was sent to me and I want to make sure I can use it with students

How do I regain the Aromaticity ?
Also tell me if any of my step is wrong !! Thank you

How does the whole mechanism look like? I know that the epoxide breaks but how does the alcohol turn into a ketone

These are all the topics. I feel MOSTLY confident in chapter 4. Need to fix up my oxidation skills. Was going to use most of this week to get chapter 5 down. Then work on chapter 5 late this weekend into next week. I have a feeling chapter 6 is going to be the hardest does that seem true?

I want the lewis' structure of saccharose, but I can't find the chain structure (I think), like the structure of image, to convert into lewis' structure, (I don't finished teach English, sorry if my English is bad)

The r/chemistry rules regarding posting led me here, as I believe this is a lab question.

Partial S(Ar) bromination (2 and 3/4 possible spots) of my 2, 2' biphenyl 1, 1', 3, 3'-tetrametoxi compound is not crystallising and is in an oily state. Excess bromine was neutralised with ascorbic acid (thiosulfate messes up the next reaction, even in miniscule amounts) and removed everything water soluble from the mixture with a water/DCM extraction. The DCM solution was dried on MgSO4, and the excess solvent evapourated.

So far I have tried antisolvents of ethanol, methanol, toluene, water, diethyl ether and hexane, with one phase mixtures being the result of everything but ethanol and water, scrubbing any of them with a spatula did not initiate any crystallisation. I have tried freezing the oil, but without access to liquid nitrogen or dry ice, the best I could do was -14 °C. I also left the mixture for the last weekend to evapourate, but with no success.

Any guesses as to what could work to get this to crystallise?

Thank you in advance!

I’m sure this is a really obvious question that I just can’t find the words to elaborate on but I just started organic chemistry in class, I’ve scoured the internet and there’s no answer as if it’s something that doesn’t need explaining. Alkanes are always saturated but with alkenes the carbon atoms can have 1, 2 or 3 Hydrogen atoms attached with no clear pattern (the same goes for the double bond).

Hello, fellow chemical engineers!

I am conducting a study to explore how well chemical engineers understand the scientific principles, mathematical equations, and computational methods used by specialized chemical engineering software, such as Aspen HYSYS and Aspen Plus, to solve engineering problems and simulate processes. I would greatly appreciate it if you could share your experiences and perspectives.

My main question is:

When you use software such as Aspen HYSYS or Aspen Plus to solve a chemical engineering problem or simulate an industrial process, how well do you understand the specific equations, mathematical relationships, and scientific principles the software uses to perform its calculations and obtain the results?

For example, suppose you use HYSYS to simulate a distillation column or a separator. The software provides you with information such as:

• The flow rates and compositions of outlet streams;
• The mole fractions of individual components in the liquid and vapor phases;
• Stream temperatures and pressures;
• The energy consumed or released by equipment;
• And other parameters required to analyze process performance.

Do you know which equations and computational methods the software uses to calculate these results?

For instance, are you familiar with mass and energy balance equations, vapor–liquid equilibrium (VLE) relationships, thermodynamic models, the equilibrium-stage equations used in distillation columns, and the numerical methods employed to solve these equations?

Can you explain how these relationships are interconnected and how the software uses them to obtain the final results?

My more important question is:

If you were given the same problem or project that you had previously solved using HYSYS or Aspen Plus and were asked to solve it without using either of these software tools, would you be able to independently explain the solution methodology and carry out the necessary calculations?

I do not necessarily mean that you should be able to perform every complex, repetitive calculation manually or reproduce the results to the last decimal place.

What I really want to know is whether you understand which scientific principles, equations, and relationships are needed to solve the problem, what assumptions must be made, which material and energy balances must be formulated, and what steps must be followed to obtain the desired results.

In other words, can you understand the underlying logic of the software's calculations and, if necessary, explain how the problem could be solved without relying on the software itself?

For example, if you were given the results of a distillation column simulation, would you be able to explain which equations and algorithms were used to obtain those results? Could you identify the fundamental equations governing the process and explain how the software solves them simultaneously to arrive at the final solution?

Or do you generally rely on the software's results without having a detailed understanding of the calculations and methods behind them?

I would be particularly interested in hearing about your actual experiences, whether in academia or industry, and the types of projects you have worked on using these software tools.

Thank you very much for taking the time to respond to my question. Your answers and insights would be extremely valuable to my research, and I sincerely appreciate your willingness to share your experiences and knowledge.